A method and apparatus for positioning a finger on a touch panel in a wet state and a touch detection apparatus are provided. The method includes: searching out suspect wet regions on the touch panel in a spacing coding manner, and determining a wet region from the suspect wet regions in a self-capacitive coding manner; traversing detection channels in the self-capacitive coding manner, and judging whether the detection channels satisfy a first condition; and if the detection channels in the wet region satisfy the first condition, determining a relative position relationship between a touch position of a finger and the wet region according to variations of feature data differences of the detection channels on the entire touch panel; or determining a relative position relationship between a touch position of a finger and the wet region according to variations of feature data differences of the detection channels outside the wet region.